无机盐对磺酸盐型双子表面活性剂溶液表面性能的影响

Effect of Inorganic Salt on surface Performances of Sulfonate Gemini Surfactant Solution

摘要:

在（30℃+0.2）实验温度下，用直接观察法、表面张力法和旋转液滴法研究了不同无机盐（NaCl，CaCl2和MgCl2）对磺酸盐型双子表面活性剂DJ溶液溶解性、临界胶束浓度（cmc）值和界面张力的影响。结果表明：磺酸盐型双子表面活性剂DJ具有良好的抗盐性，溶解度可以达到20000mg/L以上；在低盐度范围时（小于500mg/L），随着无机盐浓度的增加，表面活性升高，cmc降低；随着阳离子(Na+，Ca2+和Mg2+)价数的增加，cmc降幅增大，且Ca2+的影响大于Mg2+；在无机盐浓度达到10000mg/L时，cmc呈上升趋势；无机盐的加入使溶液界面张力先降后升，然后趋于平稳。无机盐浓度在100到1000mg/L范围内，磺酸盐型双子表面活性剂DJ溶液的界面张力可以达到最低。本研究对不同水质条件的油藏筛选合适的表面活性剂具有一定的理论指导。

Abstract:

At (30+0.2) ℃, the effect of inorganic salt, NaCl,CaCl2 and MgCl2 on solubility，cmc (Critical Micelle Concentration) and the interfacial tension of sulfonate Gemini surfactant DJ aqueous solution was investigated by the methods of direct observation, surface tension and the rotating droplets. The results showed that sulfonate Gemini surfactant DJ had highly resistance to salt while solubility was up to 20000mg /L. As the concentration of inorganic salt increased, the value of cmc and surface activity decreased below 500mg/L first, then increased when the concentration reached to 10000mg/L. With the increase of the valence of cation（Na+，Ca2+ and Mg2+）, cmc had a greater decrease and the influence of Ca2+ was more than Mg2+. Interfacial tension first descended and then rose, smoothed at last by adding inorganic salts. The low interfacial tension of sulfonate Gemini surfactant DJ appeared within a salinity range of 100-1000mg/L. The research could provide certain theoretical guidance to select out suitable surfactant for different water quality of oil reservoir.